Killing Dist pickups ?

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mbaird

mbaird
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I am running a Daytona Sensors CD-1 ignition and had a no start issue a few months ago.
So I called the tech line and they suggested my distributor pickup may be at fault. So I installed a new one and sure enough it fired right up . But now it appears I have the same issue ! Could it be bad luck with a faulty new one or could something be killing them ?

This car is just being finished up and so far it has only driven in and out of the garage and around the block once.
 
mag pickup is just that, a coil of wire around a magnetic pole. its passive....maybe this can assist in testing them
chapter-57-17-728.jpg
 
Not much can kill them but heat, added stray voltage and just plain old defective.
 
The thing that could kill them IS A FAULT IN THE IGNTION BOX. The pickup should NOT have much if any voltage/ current through it. It is essentially a magnetic generator, which sends a signal to the box. But something wrong in the box may be passing enough power through the pickup to cause failure.

What is the connector? If this system uses the usual Mopar rubber 2 wire connector, they are a suspect deal. Inspect for corrosion with a magnifier/ light, and work the connector in/out several times to scrub the terminals.
 
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This is the adapter from CD-1 to distributor

I spoke to both the Daytona Techline and Don @ FBO . The techline has not seen an issue as such but would like to get feedback on anything I discover .
Don told to check the ohms at pickup lead , Reluctor gap (.010) ,cap for tracking and to disconnect tach from feed wire . Still no fire .
I got 290 ohms thru pickup... in fact I got the same reading out of 4 different pickups I have . 1 other read 410 ohms ..

A possible common denominator is that I had recently installed a tach on both occasions...
First was an Autometer monster tach ..2nd was an old MSD tach I had . I used the tach feed from the box as instructed not directly to the coil.
 
The Ohm meter test in pickup is not very good. If it measures open, pickup is bad from broke wire or connection. One turn to turn short will fail a pickup, but cannot be measured, it will not stand out from all the other turns. The single turn short is like shorting output of a transformer, it hogs all the generated signal. Only a scope knows for sure. :)

As Del says, the connectors are not reliable. They are unsealed, and temperature cycles results loss of contact pressure.
Cleaning, tighten female contact by plier squeeze, and deoxIT may work. Buying new, gives half new contacts, may work for awhile, sounds like your problem.
 
I have tried 3 different reluctors now. Still no signal to CD unit . Urghh ! I am not looking forward to rewiring the unit and 3 rev limiters/ linelock sugnal !
 
I have tried 3 different reluctors now. Still no signal to CD unit . Urghh ! I am not looking forward to rewiring the unit and 3 rev limiters/ linelock sugnal !

Forgive my ignorance but what is the line lock signal wired into the ignition?
 
Sounds like other problem. Pista provided info on how to test with meter. Too many loads on pickup signal reduce its output. Output increases with engine speed, cranking speed is about 200 RPM at best, at 2000 the output is 10x. Most pickup issues happen when starting. A relay could be cobbled in for all the rev limter stuff, to switch in after start. Or make an amp to boost signal, or make or buy a decent optical or Hall triggered distributor.
 
I have relays wired in .

YR - this system has a 3 rev limiters.
1 for burnout activated by line lock signal
1 for launch activated by clutch release
1 for max rpm
 
The system is designed for the limiters and all is wired per instructions.

The feed from the distributor is a dedicated seperate feed into box
 
Have you tried installing an MSD tach adapter, had that same problem a few back & without the adapter it was sending ignition pulse to ground. Installed the tach adapter & the problem went way & it still running today as far as I know.
 
Have you tried installing an MSD tach adapter, had that same problem a few back & without the adapter it was sending ignition pulse to ground. Installed the tach adapter & the problem went way & it still running today as far as I know.

I didnt think I needed one using the direct tach feed on the box . I will ask the tech line .
Was it killing the pickup ?
 
I really don't remember (CRS) it's been at least 5 years or longer. I just remember that after I installed the adapter, it cranked right up. IIRC, it was one of these 2 MSD numbers; 8910 or 8920. I have no idea why, but I have the empty packages hanging on the wall above my computer.
 
Pull the distributor and chuck it up in an electric drill and spin it; you should get around 5VAC. I run Belden shielded wire for the pickup and route it away from as much other wiring as possible. The pins on the adapter may only be crimped and definitely not weather tight.
Polarity is also important. The color changes of wiring don't look right. Violet +, Green - looks reversed from the pickup.
 
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Are you sure you are damaging the pickups, or is the moving stuff around while you are replacing it temporarily fixing a bad connection some where close?
 
I am not sure the current pickup is bad . But after replacing the last one it fired right up.
Could be a coincidence ...
 
Bought 2 new LX102 pickups and installed 1 .
Still no signal to box .
While messing with this I created a short somewhere and fried the wires to the ballast.
I unwrapped the harness under hood and am tracing my short.
Last week I was sorting out all my lighting and that involved the turn signal switch . Got all the lights (signals, flashers , breaks etc.. )but no horn . So I am at the point of checking for grounds at the T signal connector and find every other pin grounds out. Is this normal ?
FSM has no schematic for the switch itself and I am finding many differing versions online.

BTW, why is there a Ground terminal on the ignition switch but no wire to it ?
 
I should mention the the Turn Signal switch is unplugged .
Maybe I should start a new thread on this .
 
Bought 2 new LX102 pickups and installed 1 .
Still no signal to box .
W

How are you determining this. Something I about mentioned earlier is, have you checked condition of the reluctor, checked for wobble/ wear in the dist shaft, and how do you set reluctor gap?

What have you done to check the pickup connector? These can be a problem, loose, corroded, etc
 
I should mention the the Turn Signal switch is unplugged .
Maybe I should start a new thread on this .


So you are saying? that you have the TS switch unplugged, and that you are checking pins to ground? NONE of the actual TS pins should be grounded. Only the horn wire (black) should ground. I'd have to look up anything else.........What year / model?
 
Del . I have tested all the reluctors for resistance and voltage . Niether seems to be a reliable test . I have used several distributors that I know work in my barracuda .

As for the signal switch . I found it odd to find them grounding as well . Since all my lighting now works properly. Horn is still not working . And I disconnected the horn ground at the wheel .
 
The Ohm meter test in pickup is not very good. If it measures open, pickup is bad from broke wire or connection. One turn to turn short will fail a pickup, but cannot be measured, it will not stand out from all the other turns. The single turn short is like shorting output of a transformer, it hogs all the generated signal. Only a scope knows for sure. :)

As Del says, the connectors are not reliable. They are unsealed, and temperature cycles results loss of contact pressure.
Cleaning, tighten female contact by plier squeeze, and deoxIT may work. Buying new, gives half new contacts, may work for awhile, sounds like your problem.

The issue with the OE distributor connector is what caused me to remove it and wire direct.
 
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